Alternators convert mechanical energy from a vehicle engine into electrical energy for consumption by the vehicle. The electrical energy produced by the alternator charges the vehicle battery and powers electrical loads on the vehicle.
The alternator generally includes a rotatable field coil positioned within a stator having a plurality of stator windings. Operation of the engine results in rotation of the field coil relative to the stator. Current flowing through the rotating field coil establishes a rotating magnetic field, which induces an AC output voltage in the stator windings. A rectifier of the alternator rectifies the AC voltage. The rectified voltage is supplied to the vehicle battery and the electrical loads on the vehicle.
The typical vehicle alternator includes a voltage regulator, which controls the voltage of the electrical signal supplied to the field coil, among other functions. In general, a higher voltage set point results in more current through the field coil and the rectified output voltage of the alternator increases. A lower voltage set point results in less current through the field coil and the rectified output voltage of the alternator decreases.
The voltage regulator of the typical alternator is usually electrically connected to an ECM (“engine control module”) of the vehicle. The ECM sends electronic signals to the voltage regulator that determine the operating state of the voltage regulator. For example, if the ECM determines that a component of the vehicle requires additional electrical power, then the ECM may send an electronic signal to the voltage regulator to increase the set point voltage. In general, the ECM sends signals to the voltage regulator, which optimize operation of the alternator for the current operating conditions of the vehicle.
The ECM and the voltage regulator are electrically connected by a wired electrical connection. The wires connecting the ECM to the voltage regulator extend from inside the vehicle cabin (where the ECM is typically located) to the alternator located in the vehicle engine compartment. Often, the wires are routed in a wire harness containing many other wires.
The wired connection between voltage regulator and the ECM is typically highly stressed. The vehicle engine compartment is an area subject to extreme condition. For example, in the summer months temperatures in and around the vehicle engine compartment may reach 120° C. In snowy climates, the salt used to treat icy winter roads is often drawn into the engine compartment and may cover most engine components, resulting in corrosion of metal components. These extreme conditions often result in corrosion and deterioration of components within the engine compartment. Moreover, the electrical connection between the voltage regulator and the ECM is stressed by movement of the engine relative to the vehicle frame during operation of the vehicle. This movement may stress the terminal or connector configured to connect the wire extending from the ECM to the alternator. Thus, the electrical connection between the voltage regulator and the ECM is highly stressed and is subject to corrosive elements, extreme high temperature, and extreme low temperatures.
The factors stressing the electrical connection between the voltage regulator and the ECM may, in some situations, result in a loss of electrical connection between the ECM and the voltage regulator caused by a break in the wire(s), a corroded terminal, or other electrical fault. When the electrical connection is lost, the ECM is unable to optimize operation of the alternator. Specifically, upon losing electrical connection with the ECM, the voltage regulator enters a default mode of operation that is suitable for vehicle operation, but causes the alternator to operate at a sub-optimal level. In the default mode the alternator may generate too much power or not enough power, because the voltage regulator is unable to receive the optimizing signals from the ECM. Moreover, operation of the alternator in the default mode may result in a rough or irregular engine idle.
Therefore, for at least the reasons set forth above, further developments in the area of vehicle alternators are desirable. It would be advantageous if such developments resulted in a more reliable vehicle electrical system. Additionally, it would be advantageous if such further developments could be implemented easily and with relatively little expense.